Increase the torque jaw taper, usually taper at 3-8, bite tube. Automatically adapt to different pipe diameters and automatically adapt to the jaw of tube applied stress caused by plastic deformation, under the effects of the reduced diameter and ensure the torque and not slip.

Pipe pliers according to the bearing capacity is divided into grade and ordinary grade two grades; according to the weight of the points is heavy, heavy, light; according to the design points for the British, American, German, Spanish, skew, chain, olecranon handle double pipe clamp, such as; petiole material according to the points for the aluminum alloy pipe wrench, cast steel pipe wrench, malleable iron pipe wrench, ball iron pipe pliers.